1. Field of the Invention
The present invention relates to an apparatus and method for verifying an utterance in a speech recognition system, and more particularly, to an apparatus and method for verifying an utterance based on multi-event detection information in a natural language speech recognition system.
2. Discussion of Related Art
In general, a speech recognition system has a probability of incorrectly recognizing an utterance, and thus an utterance verification process of determining whether to accept or reject a speech recognition result is performed.
Such a technique of determining whether a speech recognition result is correct or incorrect in order to improve the reliability of speech recognition of a speech recognition system is referred to as “utterance verification.”
An existing utterance verification system performs utterance verification based on a speech recognition result of a decoder or through first-stage utterance verification based on the recognition result of the decoder and second-stage utterance verification based on information generated by other elements constituting a recognition engine, that is, a noise processing module and a feature extraction module.
Such utterance verification involves extraction of general information from a speech recognition system and thus cannot reflect characteristics for natural language speech recognition.
From an experiment of such a natural-language utterance recognition, it is possible to know that misrecognitions occur in sections of a structure pronunciation, an interjection, sound stretching, and so on.